Braking device



p 3 1930- J. SNEED 1,776,934

BRAKING DEVICE Filed. July 7, 192a Patented Sept. 30, 1930 UNITED STATES OFFICE JOHN SNEED, OF FERNDALE, MICHIGAN, ASSIGNOB TO THE "EEI'IDLAN'U fitTEEL PBODUCT$ COMPANY, OF CLEVELAND, OHIO, A CORPORATIQN OF OHIO BRAKING- nnvrcn Application filed July 7, 1928. serial Ito. $390,954.

This invention relates to brakes and more particularly to shoe arrangement and construction and to an adjustable stop or positioning device for the shoe.

I choose to illustrate my invention in the environment of a brake having a full floating shoe comprising a relatively rigid served part and a relatively flexible servo part having adjacent ends pivotally mounted on a common anchor at least in idle position.- In such a brake, the mid portion of the shoe may swing bodily in idle position about the anchor and my invention comprises an 1mproved adustable stop for determining the idle position of the mid portion of the shoe. 1 have illustrated in my copending application Serial No. 261,7 60, filed March 15th, 1928, an adjustable stop and to that extent this invention constitutes an improvement over the device therein illustrated and described. My present invention also contemplates an improved shoe structure cooperable with the sto Ft is among the objects of my invention to arrange an adjustable stop for determining the idle position oflthe brake shoe. Another object is to arrange a stop which in 1tself is not subjected to excessive wear or deformation in the life of the brake. Another ob ect is to arrange a stop which can be cheaply made and quickly assembled. A further ob- 'ect is to arrange the stop capable. of l1m1tmg both lateral and radial movement of a brake shoe. Another object is to provide an improved brake shoe capable of high selfenergization and designed to give a soft action without abbing. A further object is to arrange a s oe which can be cheaply made and easily assembled and with which the adjustable stop may cooperate.

Other objects will appear from the following description of a preferred form of myinvention, reference being had to the accompanying drawings. The essential characteristics are summarized in the clalms.

In the drawings, Fig. 1 is an elevation of the brake and shoe assembly, and Fi 2 1s a section taken along the line 2-2 of 1g. 1.

Referring particularl to Fig. 1, I have illustrated the usual bra e drum D, the open face of which is closed by an apron or back plate A. The apron carries an anchor pin P against which adjacent ends of brake shoe S abut. The shoe comprises a relatively rigid part 1 which may be pressed from sheet stock toggle is intended to force the more flexible end of the shoe away from the anchor and into engagement with the drum so that the flexible part of the shoe serves the channel part. When the vehicle is moved backward the friction between the drum and the shoe causes the channel part to serve the flexible part and the braklng torque will be taken through the adjusting device. Retractor springs 4 and 5 are connected to the ends of the shoe and to the apron. The spring 5 may be stronger than the spring a to maintain the rigid part of the shoe on the anchor durin the usual application of the brakes when t e vehicle is moving forwardly.

' As mentioned above both ends of the shoe are pivotally supported on the anchor pin P in idle position and the mid portion of the j shoe, unless otherwise restrained, is free to swing about the anchor pin. To limit the swinging and to position the shoe in idle osition, a second point of, support is provi ed for the channel part of the shoe comprising the adjustable stop member 10, see also Fig. 2. A spring 11 is secured to the end of the outer flange of the channel part at one end and secured to the apron at the other end so that the springs 5 and 11 tend to hold the channel part in a determinable position against the anchor pin and a ainst the adjustable stop. The effective ength of the flexible band-like part of the'shoe 2 is adjusted-through the adjusting device 3 so that its clearance is determined by adjusting its overall length.

The adjustin stop comprises essentially a circular disc ike part having an annular cylindrical brim 12 with a concentric sleeved opening 13. The inner end of the sleeve engages to apron as at 14; and spaces the body of the disc-like part therefrom. The member 10 may be stamped from sheet stock in a simple operation. Extending through the opening 13 and through a suitable aperture in the apron is a bolt having an eccentric shank 21. The bolt 20 may have an enlarged head 22 so that lateral movement of the member 10 is restricted betweenthe head 22 and the inner surface of the apron. The other end of the bolt 20 may be reduced and threaded and slotted as at 23. The bolt may be secured by a nut 24 and lock washer 25 in any desired position about its own axis so that the effective center of the member 10 may be moved radially of the apron according to the position of eccentricity ofthe shank 21. The sleeve 13 may have a close running fit with the eccentric shank of the bolt so that in the course of the life of the brake the member 10 may rotate and present various parts of its surface to the inner face of the shoe.

I The disc like bod of the member 10 extends parallel to an lies adjacent 'to the inner side flange of the channel and serves to limit movement of the shoe away from the apron. It will be noted that the apron is indented as at 30 and the spring 11- tends to draw the shoe into contact with the indented portions of the apron. The outer cylindrical ange part of the member 10 engages the web of the channel part of the shoe as at 26 and limits the radial movement of the shoe according to the position of the eccentric shank of the bolt 20. In the arrangement illustrated herewith the inner flange of the channel is notched slightly as at 31 to permit reduction of the diameter of the disc like part of the member 10.

In operation as mentioned above the channel part ofthe shoe is swung into engagement by the flexible part and necessarily moved away from the member 10. When the brake is released the springs 5 and 11 draw the channel part back into contact with the member 10 while swinging the channel part about the anchor pin P as a center. Durin this motion of the channel part, contact wlth the member 10 is not strictly radial and may be at such an angle from a radial line as to tend to rotate the member 10 about the shank 21 of the bolt. This slight rotation for each application of the brake causes the member 10 to present a new surface for contact with the shoe so that the wear between contacting surfaces is reduced to a negligible amount.

As the brake lining wears the total effective length of the shoe may be increased through the adjusting device 3 so that the circle defined by the inner side of the linin supporting part of the shoe is increase When this is done, the bolt 20 may be rotated to a new position so that the eccentric shank 21 will move the center of the disc like member 10 outwardly to locate the idle position of the channel part of the shoe. v

The particular and preferred form of the adjusting device 3 shown herein isfully disclosed and claimed in my copending application, Serial No. 281,062 filed May 28th, 1928. Suflice to say that the part 3 is fixed to the shoe and receives a circumferentially extending portion 3B of the part 30, the part 36 engaging the anchor pin P and the toggle T. A bolt 3D extending through the part 3A and the circumferential portion 3B of the part 3C serves to clamp the parts together whereby they can be adjustably p0- sitioned and secured relative to each other in any position desired. Thus the effective length of the shoe may be varied by loosening the bolt 3D, positioning the parts as desired, and thereafter receiving them in the desired position.

From the foregoing it appears that my brake is sifiiple in construction; that the shoe arrangement insures high self-energization and that the rigidit of the channel part prevents grabbing. t will further appear that the idle position of the whole shoe may be definitel established both by changing the total e ective length of the shoe and by varying the position of the adjustable stop member; that the stop member itself is simple in construction and designed for a long accurate service; that all the parts may be economically manufactured and assembled, and that while I have illustrated and described a preferred form of my invention, I

do not care to be limited thereto or in any manner, other than by the claims appended hereto.

I claim 1. A retractor stop comprising a mounting associated with a relatively fixed part of the brake and having an eccentrically formed part, and a member with a circular periphery and a concentric bearing part pivotally mounted on said eccentrically formed P 2. A retractor stop for a brake havin a back plate comprising a disc like mem r having a circular peripher having one part supported y the back plate and a second part formed eccentric of the first part and pivotally and concentrically carrying said disc like member.

3. A retractor stop for a brake having a back plate comprising a member having a circular periphery and a central opening concentric with the periphery and a member loo and a member Y .ing the shoe part of the brake and a sleeve part associated with said mounting.

5. A retractor stop for a brake adapted to be pivotally mountedon a relatively 'fixed part of the brake having a circular periphery with a cylindrically. formed brim for engaging the shoe part of the brake and a central opening concentric with said cylindrical part and associated with said mounting.

6. A retractor stop for a brake shoe co m prising amember having a disc like body part with a cylindrically flanged periphery and a concentric centrally sleeved o ening, said cylindrical part engaging the s 0e and said sleeved opening constituting a bearing for mounting said member. f

7. A retractor stop $01 a brake shoe comprising a member having a disc like body part with a cylindrically flanged periphery and a centrally sleeved opening, said cylindrical part engaging the shoe and said sleeved opening'constitutmg a bearing for'mounting said member, in combination with an eccentric mounting for said member.

8. A brake having a back plate, a shoe and a tractor stop for the shoe comprising a disc like member with a cylindrically flan ed periphery extending away from the back plate and a tubular sleeved central part extending toward the back plate and spacing the disc like part therefrom, and an eccentric mount-- ing carried by the back plate and extending through said tubular sleeved part.

9. A brake having a back plate, a shoe, and a retractor stop for the shoe comprising a disc like member, and a tubular sleeved central part extending toward the back plate and spacing the disc like part therefrom, and an eccentric mounting carried by the back plate and extending through said tubular sleeved art; p 10. A brake havinga back plate, a shoe, and a retractor sto comprising a disc like part engageable with the "shoe along its periphery and a tubular sleeved part spacing the disc like part away from the back plate and constituting a bearing for mounting said stop.

11. A brake having aback plate, a shoe, and a retractor stop comprising a disc like part engageablewith the shoe along its periphery and a concentric tubular sleeve having an opening coaxial with the periphery and spacing the disc like part away from the back late.

12. a brake having a back plate and a shoe, a retractor stop for theshoe comprising a substantially disc like member. engaging.

the shoe at its periphery, and having a central opening formed concentric with the periphcry, a bolt having a part extending through the back plate and having an eccentric shank extending through the opening in the disc like member and means for securing said bolt relative to said back plate.

.13. In a brake having a back plate and a shoe, a retractor stop for theshoe comprising asubstantially disc like member engaging the shoe at its periphery, and having a central opening formed concentric with the periphery, a bolt having a part extending through the back plate, leaving an enlarged head and having an eccentric shank extending through the opening in the disc like member.

14. In a brake the combination of aback plate, a shoe of channel section of uniform depth having inwardly extending side flanges, an adjustable stop member comprising a bolt with an eccentric shank carried by the apron, a disc likepart mounted on the eccentric shank, the disc like pait extending parallel and adjacent to one of said side flanges, the edge of said side flange being cut away to clear said bolt.

15. In a brake the combination of a back plate, a Shoe of channel'section having inwardly extending side flanges, an adjustable stop member comprising a bolt with an eccentric shank carried by the back plate, a disc 7 like part mounted on the eccentric shank and spaced from the back plate, the disc like part extending parallel and between the s1de flanges, the edge of oneof the side flanges being cut away to clear said bolt.

16.. In a brake the combination of a back plate carrying an anchor pin, a substantially annular shoe comprising a part channeled in cross section with inwardly extending side flanges of uniform depth, a retractor stop member for'the channel part of the shoe compart adjustably secured in the apron and a disc-like member having an integrally formed tubular sleeved part rotatably mounted on the said eccentric part with the periphery of the disc-like member engaging the lining supf porting part of the shoe and lying adjacent but spaced from one of said side flanges of p the shoe. a

18. In a brake the combination of a back plate having at least one raised part, a shoe having a channel part with inwardly extending side flanges, one of said side flanges contacting with the raised part of the back plate and being spaced from the back plate thereby, resilient means for urging the shoe onto said raised part of the back plate, a retraction stop member comprising a disc like part having its periphery engaging the lining supporting part of the shoe, said-disc like part being eccentricallymounted relative to the back plate and said disc like part lying parallel and adjacent the side flange of the chan nel part and limiting movement of away from the back plate.

19. In a' brake the combinationxof the shoe .5. back plate having at least one raised part, a shoe having'a'channe'l part. with inwardly extending side flanges, the edge of the shoe contacting with the raised'part of the back plate and being spaced from theback plate thereby, a retraction stop member comprising-a dlsc-like =pfart having its periphery engaging the lining supporting partv of the shoe,

. nel part andlimiting movement of the said disc like part being eccentrically mounted relativefto the back' plate and spaced therefrom and said disc-like 'part lying parallel an'dadjaceiit a side'fiange of the chfins oe away from the back plate. 1

20. Ina brake the'com'bination of a fixed part, a shoe part movable relative thereto, means includingJa-rOtata'ble disc adjustably and pivotally -siipported by one of said parts and engaging the other of said parts to limit relative radial, movement therebe'tween,

means for limiting the axial movement be-- tween said parts and resilient means acting to move said'parts toward each other.

.21. In a brake the combination of a back.

plate, a shoe, a member having a disc like portion engaging the shoe for limiting in ward radial movement thereof, means for pivotally sup orting said member, said means bein a j u'stably secured to said backing plate W ereby various determinable positions for said shoe may be established relative to said backing plate, and means for 1 holding said member against axial movement relative to said backing plate.

1 22. Aretractor stop for a brake having a back plate comprising a member having a circular periphery and a central opening concentric with the periphery, a member having a part supported by the back plate and a second part formed eccentric of the first part and extending through the opening in said first member for rotatably supporting it, and means for limiting axial movement between. said first member and said back plate.

23. In a brake the combination of a back plate having a-circular aperture, a shoe hav- "ing an arcu'atelining supporting part, a

member having a cylindrical body part. and

'said aperture in'said back'plate,means cooperating with said shank for securing said member in any fixed position relative to said back plate, a disc like member having a central opening rotatably mounted on said member and spaced from said back plate and having peripheral contact with the lining supporting part of said shoe, .and means for 'holding said disc like member against axial movement toward or away from said back ,plate 'while permitting "rotatable movement relative to said first named member.

' 24. In a brake the combination of a back plate, "a shoe having an inwardly extending radial flange and an arcuate lining supporting part,ea' freely rotatable disc-like member lying substantially parallel tosaid'back plate and peripherally engaging the lining supporting part of said shoe for limiting the inward radial movement thereof, means including an axis for said member adjustably positionable relative to said back plate' and secured theretoymeans engageable with said flange for limiting the axial movement thereof and resilient means 'urging said shoe toward said back plate.

, 1- 25. In 'a brake the combination of a shoe having an arcuate lining supporting part 'and an inwardly extending radial flange, a

back plate, a freely rotatable disc like member pivotally mounted on a central axisv 2 III-tGStl HI'OIIY whereof, I hereunto afiix my signature.

JOHN ISNEED.

a reduced eccentric. shank-extending through 

